CSS architecture with React that also can be themed

I'm currently building out a large React app. Css, has never been my strong point. But now CSS has sass / cssNext / inline styles with React. I've been using BEM with sass, but as my other applications have grown huge even that starts to break down. Especially when you had on the ability to "re-skin" or "theme" the pages outside of the primary color schemes etc..

so -- can someone point me to a proven way to create css with react that can scale very well, and allows for custome theme'ing when people want to borrow my components. For instance,

<MyComponent />
// this component has its styles but lets say Joe Schmoe wants be import
// it? But, Joe wants to overlay his custom styles?
// Is there a new paradigm that allows for an overlay or reskin within the component?

Or even the idea of the whole application being skinnable some time down the line. I know this is sorta a very base question, but whenever I build out projects my pain points also seem to be the CSS - so I want to know what really works.

I'm one of the maintainers of ElementalUI, a React component library, and we've been trying out all the different ways of styling for the past 6-12 months. (!) You name it, we've tried it. (I talked about my experiences with some of the most popular libraries during my ReactNL keynote and where they break down)

The issue is that none of the current styling libraries have built-in support for theming at all. You can do it with most of them in a very hacky, non user-friendly way, but that's not what you want when you distribute a component, right?

That's why we built styled-components. styled-components has a bunch of interesting properties, and one of them is that theming is directly built into the library, making it the perfect choice for building distributable components!

Here is the short explanation, though I encourage you to go through our documentation which explains everything!

Now your Button will take the theme it gets passed and change it's styling based on that! (you can also provide defaults via defaultProps)

That's the gist of styled-components and how it helps to build distributable components!

We have a currently WIP doc about writing third-party component libraries which I'd encourage you to check out, and of course the normal documentation is a good read too. We've tried to cover all the bases, so if you see anything you dislike or that you think is missing please immediately let us know and we'll discuss!

If you have any other questions about styled-components feel free to reply here or reach out on Twitter. (@mxstbr)

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